[70] For a fuller account of the different modes of dream-interpretation, see my article "Dream," in the ninth edition of the Encyclopædia Britannica.
[71] For a fuller account of the reaction of dreams on waking consciousness, see Paul Radestock, Schlaf und Traum. The subject is touched on later, under the Illusions of Memory.
[72] For an account of the latest physiological hypotheses as to the proximate cause of sleep, see Radestock, op. cit., appendix.
[73] Plutarch, Locke, and others give instances of people who never dreamt. Lessing asserted of himself that he never knew what it was to dream.
[74] The error touched on here will be fully dealt with under Illusions of Memory.
[75] For a very full, fair, and thoughtful discussion of this whole question, see Radestock, op. cit., ch. iv.
[76] This may be technically expressed by saying that the liminal intensity (Schwelle) is raised during sleep.
[77] See Wundt, Physiologische Psychologie, pp. 188-191.
[78] There is, indeed, sometimes an undertone of critical reflection, which is sufficient to produce a feeling of uncertainty and bewilderment, and in very rare cases to amount to a vague consciousness that the mental experience is a dream.
[79] Observations on Man, Part I. ch. iii, sec. 5.